Developing Self-Assembled Starch Nanoparticles in Starch Nanocomposite Films

Starch nanopartides (SNPs) are synthesized by different precipitation techniques using corn starch, and SNP films are prepared by the evaporation casting method. The morphological study is investigated by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The distribution and sizes of precipitated SNPs after synthesizing are discovered by these methods as well. The crystallinity of the SNPs is studied by the X-ray diffractometry (XRD) method that demonstrates reduction compared to neat starch granules, and it is changed from A-style to V-H-style after precipitation. The chemical bonding of different SNPs after the nanoprecipitation is analyzed by Fourier transform infrared spectroscopy (FT-IR). Thermogravimetric analysis (TGA) demonstrates the decomposition of starch nanopartides and the starch matrix that is related to the depolymerization of carbon chains in the range of 260 to 350 degrees C. The mechanical properties of the SNP films versus the temperature changing are discovered by dynamic mechanical analysis (DMA). The water contact angles of SNP films are measured using a goniometer, and the results showed the hydrophobic surfaces of the prepared films. Our study indicates that SNPs have a promising impact on the properties of corn starch films, which would be useful in biodegradable packaging material.

Automated summary

Starch nanopartides (SNPs) were synthesized and characterized in terms of chemical structure, crystallinity, and mechanical properties. The results showed that SNPs exhibited differences in these properties compared to conventional starch, and the prepared films had hydrophobic surfaces.